[PATCH 1/9] drm/fourcc: Add macro to check for the modifier vendor

[Simon Ser]

Can we instead have a macro/function to get the vendor? This would be
useful elsewhere as well, see drmGetFormatModifierVendor in a recent-ish
libdrm patch [1].

[1]: https://gitlab.freedesktop.org/mesa/drm/-/merge_requests/108/diffs#91ecb12b27c7154b26013bb95e17a5cc24ea443e_947_947